title: Infantile hypophosphatasia without bone deformities presenting with severe pyridoxine-resistant seizures.
abstract: An infant carrying a heterozygous c.43_46delACTA and a heterozygous c.668 G>A mutation in the ALPL gene with hypophosphatasia in the absence of bone deformities presented with therapy-resistant seizures. Pyridoxal phosphate was extremely high in CSF and plasma. Pyridoxine treatment had only a transient effect and the severe encephalopathy was fatal. Repeated brain MRIs showed progressive cerebral damage. The precise metabolic cause of the seizures remains unknown and pyridoxine treatment apparently does not cure the epilepsy.
authors.affiliation: Department of Pediatric Neurology, Clinical Genetics, Metabolic Disorders, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
authors.forename: Marieke G A
authors.initials: MGA
authors.lastname: de Roo
authors.affiliation: Laboratory of Genetic Metabolic Diseases, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Nico G G M
authors.initials: NGGM
authors.lastname: Abeling
authors.affiliation: Department of Radiology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Charles B
authors.initials: CB
authors.lastname: Majoie
authors.affiliation: Department of Pediatric Neurology, Clinical Genetics, Metabolic Disorders, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
authors.forename: Annet M
authors.initials: AM
authors.lastname: Bosch
authors.affiliation: Department of Neurology and Clinical Neurophysiology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Johannes H T M
authors.initials: JHTM
authors.lastname: Koelman
authors.affiliation: Department of Pediatric Neurology, Clinical Genetics, Metabolic Disorders, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
authors.forename: Jan M
authors.initials: JM
authors.lastname: Cobben
authors.affiliation: Laboratory of Genetic Metabolic Diseases, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Marinus
authors.initials: M
authors.lastname: Duran
authors.affiliation: Department of Pediatric Neurology, Clinical Genetics, Metabolic Disorders, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands. Electronic address: b.t.pollthe@amc.uva.nl.
authors.forename: Bwee Tien
authors.initials: BT
authors.lastname: Poll-The
mesh_terms: D000469:Alkaline Phosphatase / Q000235:genetics; D004351:Drug Resistance; D004827:Epilepsy / Q000150:complications / Q000401:mortality / Q000473:pathology*; D006801:Humans; D007014:Hypophosphatasia / Q000097:blood / Q000134:cerebrospinal fluid / Q000235:genetics* / Q000401:mortality / Q000473:pathology*; D007223:Infant; D008297:Male; D011732:Pyridoxal Phosphate / Q000097:blood / Q000134:cerebrospinal fluid; D011736:Pyridoxine / Q000008:administration & dosage*; D012640:Seizures / Q000235:genetics / Q000473:pathology
chemical_list: D011732:Pyridoxal Phosphate; D000469:Alkaline Phosphatase; D011736:Pyridoxine
keywords: Alkaline phosphatase; Encephalopathy; Hypophosphatasia; Pyridoxine therapy; Therapy resistant seizures